DS1744-70IND

Real Time Clock Overview

The DS1744-70IND is a Y2K-compliant, nonvolatile timekeeping RAM integrating a real-time clock/calendar and 32k x 8 SRAM. It operates at 5V with an industrial temperature range of -40°C to +85°C. The device features a parallel interface and includes an integrated lithium energy source, crystal, and power-fail control circuit within a 28-pin EDIP package. RTC registers reside in the top eight RAM locations, accessed via standard static RAM commands. Data retention exceeds 10 years without power.

Real Time Clock Feature Summary

• Integrated NV SRAM (32k x 8), RTC, crystal, and lithium battery
• Y2K compliant with automatic leap-year compensation valid to 2100
• Power-fail write protection and battery voltage-level indicator flag
• Double-buffered clock registers prevent data corruption during updates

Real Time Clock Applications

• Industrial systems requiring precise timekeeping and nonvolatile storage
• Embedded controllers needing Y2K compliance
• Data logging applications with intermittent power supply

Real Time Clock Procurement Notes

Verify the specific suffix IND confirms the -40°C to +85°C industrial grade. Confirm the package type matches the required board layout, as this model uses a 28-pin encapsulated DIP module. Ensure the system design accounts for the separate PowerCap option if surface-mount assembly is preferred over through-hole installation.

Real Time Clock Selection Notes

Select the DS1744-70IND for 5V logic systems requiring 32KB of nonvolatile memory alongside timekeeping. Compare against the DS1744P variant if surface-mount compatibility with a separate PowerCap module is necessary. Verify that the parallel interface timing requirements align with the host microcontroller's bus speed.

Real Time Clock Part Context

This component belongs to the DS174x family of nonvolatile timekeeping RAMs. It shares pinouts with other densities in the series, allowing for density upgrades without redesigning the PCB. The 'IND' suffix specifically denotes the industrial temperature rating, distinguishing it from commercial variants.

Real Time Clock Replacement Considerations

Direct replacements include other DS1744 variants with different temperature ranges or voltages, provided the interface remains compatible. Cross-density parts like the DS1747 are pin-compatible but offer different storage capacities.